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:sescape

:sescape

type: keyword
location: built-in
source file: xlread.c
Common LISP compatible: no
supported on: all machines

SYNTAX

:sescape

DESCRIPTION

:SESCAPE is an entry that is used in the *READTABLE*. *READTABLE* is a system variable that contains XLISP's data structures relating to the processing of characters from the user (or files) and read-macro expansions. The existance of the :SESCAPE keyword means that the specified character is to be used as a single escape character. The system defines that the the vertical bar character \ is the only defined :SESCAPE character.

EXAMPLES

(defun look-at (table)                  ; define a function to 
 (dotimes (ch 127)                      ;   look in a table
  (prog ( (entry (aref table ch)) )     ;   and print out any     
    (case entry                         ;   entries with a function
      (:SESCAPE                         ;
          (princ (int-char ch)))        ;
      (T            NIL))))             ;
 (terpri))                              ;
(look-at *readtable*)                   ;  prints  \ 

CAUTION: If you experiment with *READTABLE*, it is useful to save the old value in a variable, so that you can restore the system state.


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